Gather the marjoram, parsley, bay leaf and thyme in a piece of cheesecloth and tie it into a bundle with kitchen string (alternatively, tie the herbs together with a leek leaf).
Melt 4 tablespoons of the butter in a large pot over medium heat. Add the bacon, garlic and onions and cook until the garlic is soft and the onions translucent, 6 to 8 minutes. Remove from the pot.
Increase the heat under the pot to medium-high and add 2 tablespoons of the butter.
Sprinkle the beef with 2 tablespoons salt and 2 teaspoons pepper. Working in batches if necessary, add the beef to the pot and sear until browned on all sides. Reduce the heat to medium and return the bacon, onions and garlic to the pot.
Add the apple cider vinegar and cook, scraping up the browned bits from the bottom of the pot with a wooden spoon until reduced. Add the remaining 2 tablespoons butter and let melt. Add the flour and cook until everything is coated and there is a nutty aroma.
Add the beer, mustard and sirop de Liege; stir to combine. Add the bouquet garni. Bring the carbonnade to a simmer and cook until tender, 45 minutes.
Remove the carbonnade from the heat and let rest for 45 minutes. Remove the bouquet garni, reheat and serve.
Sirop de Liege is a pear and apple reduction popular in the Belgium. Other apple or pear reductions can be used instead. Some are imported from the Netherlands and called apple or pear "stroop." If you can't find any, use brown sugar instead.
This recipe was provided by a chef, restaurant or culinary professional. It has not been tested for home use.
Recipe courtesy of Taste of Belgium , Cincinnati, OH